4

When I execute the code in c# and java, I get different output. In c#, got the output 254 but in java got the output -2. Why does it behave differently in term of output? But I want the same output in java means I want output 254.

In c# code:

static void Main(string[] args)
{
     byte value = 1;
     System.Console.WriteLine("Value after conversion {0}", (byte)(~value));
}

Output : 254

In Java code: 

public static void main(String[] args) {
        byte value = 1;
        System.out.println((byte)(~value ));
}

Output : -2

Soner Gönül
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user3906847
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    Helpful: [How does the bitwise complement (~) operator work?](http://stackoverflow.com/questions/791328/how-does-the-bitwise-complement-operator-work) – Soner Gönül Nov 14 '14 at 09:07

2 Answers2

10

In C# byte denotes an unsigned 8-bit integer value, i.e. its range is 0-255. In Java, however, a byte is a signed 8-bit integer value, i.e. its range is -128-127. -2 (signed) has the same binary representation as 254 (unsigned).

Hoopje
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  • I would also emphasize that the operator `~` works the same in Java and C#, the only difference is in how `byte` is converted to String in Java and C#. – kajacx Nov 15 '14 at 19:47
0

To get an unsigned 8-bit value in Java you need to do & 0xFF

Try

System.out.println(~1 & 0xFF);

or

System.out.println((byte) ~1 & 0xFF);
Peter Lawrey
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